1. Field of the Invention
The present invention relates to a 4-cycle engine.
2. Description of the Prior Art
In recent years, a 4-cycle engine with two cylinder axes disposed in a V-shape has been proposed, which includes an electronically controlled type fuel injection system (for example, see Japanese Utility Model Application Laid-open No.127779/90). In this engine, a substantially Y-shaped distributing type intake pipe is disposed inside a V-bank, and a single injector is disposed upstream from an junction of the intake pipe, so as to supply a fuel.
In the above prior art engine, no special consideration is taken into account for reducing the size of an intake device upstream from the injector and thus, there is a problem that an engine becomes large due to such intake device.
In general, a 4-cycle marine engine is used in an environment where it is liable to be rusted easily than other engine for a vehicle and thus, many parts of aluminum alloy and stainless steel are employed. For example, a cam pulley forming a portion of a valve-operating system is made of aluminum alloy. Therefore, in order to take out a spark timing pulse from the rotation of the cam pulley, a metal piece of a magnetic material is secured to an inner peripheral surface of a rim portion of the cam pulley, and a picking-up coil is disposed so that it is opposed to the metal piece.
With the above construction, however, only one magnetic material is attached to one cam pulley. For example, in a 4-cycle engine including an electronically controlled type fuel injection system, it is difficult to take out a timing pulse for injection of a fuel in addition to the above-described spark timing pulse.